Modified asphalt as well as preparation method and application thereof

Abstract

The invention discloses modified asphalt as well as a preparation method and application thereof. The modified asphalt comprises the following components: matrix asphalt, rubber powder, a warm mixing agent and an odor removing agent, wherein based on the weight of the matrix asphalt, the content of the rubber powder is 15%-20%, the content of the warm mixing agent is 1%-5%, and the content of the odor removing agent is 0.1%-1%. And heating the matrix asphalt, and mixing the heated matrix asphalt with the rubber powder, the warm mixing agent and the odor removing agent. The modified asphalt has excellent environmental protection performance (especially smoke suppression and deodorization performance), excellent basic performance of the asphalt can be ensured, the usability is high, and the preparation process is simple.

Description

Technical Field

[0001] The invention relates to modified asphalt and a preparation method and application thereof. Background Art

[0002] In recent years, the number of cars in China has increased dramatically, and more and more tires have been scrapped. With the implementation of the national "dual carbon" strategy and the improvement of people's awareness of environmental protection and health, the effective comprehensive utilization technology of waste tires, one of the bulk solid wastes, has received more and more attention. Processing waste tires into rubber powder for asphalt modification can effectively reduce its impact on the environment. It can not only reduce the total use of high-energy asphalt products, but also effectively improve the road performance of asphalt mixtures. However, rubber asphalt produces toxic fumes with a foul odor during production and construction, which seriously limits the large-scale promotion and application of rubber asphalt.

[0003] The existing patent CN116814085A discloses a deodorizing rubber asphalt composition, which further absorbs typical asphalt odor-causing substances by adding a deodorizer, effectively adsorbs benzothiazole in the rubber asphalt, plays a deodorizing role, and reduces the emission of odorous substances during the use of rubber asphalt. However, it still has the defects of limited deodorizing performance and may affect the basic performance of asphalt.

[0004] Therefore, there is an urgent need for a modified asphalt that is environmentally friendly and has excellent basic properties. Summary of the invention

[0005] In order to overcome the defects of existing modified asphalt that it is easy to produce harmful gases and odors, the present invention provides a modified asphalt and its preparation method and application. The modified asphalt has strong environmental protection performance (especially excellent smoke suppression and deodorization performance), while also ensuring excellent basic asphalt performance, strong usability, and simple preparation process.

[0006] The present invention provides a modified asphalt, which comprises the following components: base asphalt, rubber powder, warm mix agent and deodorant; wherein:

[0007] Based on the weight of the matrix asphalt, the content of the rubber powder is 15%-20%, the content of the warm mix agent is 1%-5%, and the content of the deodorant is 0.1%-1%.

[0008] In some embodiments, the base asphalt is not limited in any way and any commercially available base asphalt may be used, such as Jingbo 70 asphalt.

[0009] In some embodiments, in the modified asphalt, the weight percentage of the base asphalt is 90%-95%.

[0010] In some embodiments, the warm-mix agent includes one or more of a polyolefin warm-mix agent, a viscosity-reducing warm-mix agent, and a surfactant-type warm-mix agent; preferably, the warm-mix agent includes one or more of WSG-H02, Sasoflex, and Sasobit.

[0011] In some embodiments, the weight percentage of the warm mix agent is 3% based on the weight of the base asphalt.

[0012] In some embodiments, the deodorant comprises a liquid deodorant and / or a powdered deodorant.

[0013] Wherein, the liquid deodorant preferably comprises alcohol, and the alcohol is more preferably plant alcohol and / or industrial alcohol.

[0014] The plant alcohol may refer to alcohol extracted from plants or obtained through plant fermentation, also known as plant ethanol. In nature, plants can convert sugars into ethanol through the fermentation process, which is one of the main sources of plant alcohol. The mechanism of action of plant ethanol in powdered deodorants may include physical adsorption and chemical reaction. On the one hand, ethanol molecules can penetrate around odor molecules and adsorb them through physical effects such as van der Waals forces; on the other hand, the hydroxyl group (-OH) in the ethanol molecule may react chemically with the odor molecules, thereby changing their chemical properties and removing the odor.

[0015] The industrial alcohol may refer to alcohol obtained through petrochemical reactions or synthesis gas fermentation, also known as industrial ethanol.

[0016] The powdered deodorant preferably comprises a porous adsorbent material, such as one or more of activated carbon, zeolite, porous calcium phosphate and silica gel.

[0017] In some embodiments, the deodorant has a content of 0.2%, 0.4% or 0.6% based on the weight of the base asphalt.

[0018] In some embodiments, in the modified asphalt, the weight ratio of the warm mix agent to the deodorizer is 2.5:1-15:1, preferably 2.5:1-10:1, such as 5:1 or 7.5:1.

[0019] In some embodiments, the rubber powder has a mesh size of 40-80 mesh.

[0020] In some embodiments, the rubber powder is waste tire rubber powder.

[0021] The present invention also provides a method for preparing the modified asphalt as described above, which comprises the following steps:

[0022] The base asphalt is heated and mixed with the rubber powder, warm mix agent and deodorant to obtain the modified asphalt.

[0023] In some embodiments, after the base asphalt is heated, it is sequentially mixed with the rubber powder, warm mix agent, and deodorizer.

[0024] In some embodiments, the heating temperature is 150-180°C, such as 170°C.

[0025] In some embodiments, the mixing is stirring mixing.

[0026] In some embodiments, the mixing time is 0.5-3 hours.

[0027] In some embodiments, the mixing temperature is 150-180°C, such as 170°C.

[0028] In some embodiments, the mixing speed is 250-2000 rpm, such as 1000 rpm.

[0029] In some embodiments, the mixing step further includes a purification step; preferably, the purification method is filtration.

[0030] The present invention also provides an application of the modified asphalt as mentioned above in a road pavement structure.

[0031] On the basis of being in accordance with the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present invention.

[0032] The reagents and raw materials used in the present invention are commercially available.

[0033] The positive and progressive effects of the present invention are:

[0034] The present invention adds a specific amount of warm mix agent and deodorizing agent to the existing rubber asphalt, and basically does not affect the basic properties of the base asphalt itself while maintaining excellent smoke suppression and deodorizing properties. The warm mix performance, smoke suppression and deodorizing properties of the obtained modified asphalt can even be further improved through the coupling effect of the two. It has good environmental protection performance and usage performance, can significantly reduce the generation of harmful gases and odors during asphalt construction, has a significant environmental protection effect, and has a high value for promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 These are the results of needle penetration and softening point analysis in Effect Example 1.

[0036] Figure 2 It is the rutting factor analysis result in effect embodiment 1.

[0037] Figure 3 This is the high temperature failure temperature analysis result in effect embodiment 1.

[0038] Figure 4 This is the rotational viscosity analysis result in Effect Example 1.

[0039] Figure 5 This is the infrared spectrum analysis result in Effect Example 2.

[0040] Figure 6 This is the infrared spectrum data processing result in effect embodiment 2.

[0041] Figure 7 These are the analysis results of ammonia generated by heating asphalt in Effect Example 3.

[0042] Figure 8 The concentration of ammonia generated by heating the asphalt obtained at different deodorant dosages in Effect Example 3.

[0043] Fig. 9 These are the results of analyzing nitrogen oxides produced by heating asphalt in Effect Example 3.

[0044] Fig.10 The concentration of nitrogen oxides generated by heating the asphalt obtained at different deodorant dosages in Effect Example 3.

[0045] Fig.11 These are the results of analyzing hydrogen sulfide produced by heating asphalt in Effect Example 3.

[0046] Fig.12 The concentration of hydrogen sulfide generated by heating the asphalt obtained at different deodorant dosages in Effect Example 3.

[0047] Fig.13 This is the analysis result of sulfur dioxide produced by heating asphalt in Effect Example 3.

[0048] Fig.14 The concentration of sulfur dioxide produced by heating the asphalt obtained at different deodorant dosages in Effect Example 3.

[0049] Fig.15 The concentration of sulfur dioxide generated by heating the asphalt obtained at different stirring times in Effect Example 3.

[0050] Fig.16 The sulfur dioxide concentration generated by heating the asphalt obtained at different stirring speeds in Effect Example 3. DETAILED DESCRIPTION

[0051] The technical solution of the present invention is further illustrated by the following examples.

[0052] The experimental methods used in the following examples are conventional methods unless otherwise specified. The materials, reagents, methods and instruments used are conventional materials, reagents, methods and instruments in the art unless otherwise specified, and can be obtained through commercial channels by those skilled in the art.

[0053] Unless otherwise specified, the specific information of each raw material in the following examples and comparative examples is as follows:

[0054] Base asphalt - Base asphalt Jingbo 70; Rubber powder - 40 mesh; Warm mix agent - Sasobit; Liquid deodorizer - Plant ethanol (Shandong Jinli Chemical Co., Ltd.); Powdered deodorizer - Activated carbon.

[0055] Experimental Example 1

[0056] The modified asphalt of this embodiment is prepared by the following preparation process:

[0057] 1. Raw materials and dosage: base asphalt Jingbo 70, rubber powder (based on the weight of base asphalt, 20%), warm mix agent Sasobit (based on the weight of base asphalt, 3%), liquid deodorizer (based on the weight of base asphalt, 0.2%).

[0058] 2. Specific steps:

[0059] S1. Heating: Heat the base asphalt to 170°C to make it liquid.

[0060] S2, mixing: rubber powder, warm mix agent and liquid deodorant are added to the base asphalt obtained in step S1 in order, and the raw materials and the base asphalt are completely mixed using a conventional mixer, with a specific stirring time of 30 minutes, a stirring temperature of 170° C. and a stirring speed of 1000 rpm.

[0061] S3. Purification: Use conventional filters to purify asphalt, remove impurities and insoluble substances, and improve the purity of asphalt.

[0062] Examples 2-18 and Comparative Examples 1-39

[0063] On the basis of keeping other conditions the same as those in Example 1, referring to the contents of Table 1, the modified asphalts or asphalts of Examples 2-18 and Comparative Examples 1-39 were prepared respectively.

[0064] The meaning of the amounts in the table is: the relative amount of each raw material based on the weight of the base asphalt.

[0065] Table 1

[0066]

[0067]

[0068]

[0069] Effect Example 1 Determination of basic properties of asphalt

[0070] (1) Needle penetration measurement

[0071] The asphalt obtained in Examples 1-6 and Comparative Examples 1-9 was tested respectively, and two groups of samples were tested in parallel. The testing standard was "Testing Procedure for Asphalt and Asphalt Mixture in Highway Engineering" (JTG E20-2011). The results are as follows: Figure 1 shown.

[0072] Depend on Figure 1 It can be seen that compared with rubber asphalt (AR), the deodorizer (corresponding to DAR) has no obvious effect on its penetration. It needs to be further combined with a warm mix agent (corresponding to DWMAR) to improve its penetration, increase its consistency, make its texture softer, and better resist rutting and flow deformation.

[0073] (2) Softening point determination

[0074] The asphalt obtained in Examples 1-6 and Comparative Examples 1-9 was tested respectively, and two groups of samples were tested in parallel. The testing standard was "Testing Procedure for Asphalt and Asphalt Mixture in Highway Engineering" (JTG E20-2011). The results are as follows: Figure 1 shown.

[0075] Depend on Figure 1 It can be seen that, compared with rubber asphalt (AR), the deodorizer (corresponding to DAR) has no obvious effect on its softening point, while further combining with the warm mix agent (corresponding to DWMAR) will reduce its softening point to a certain extent, making it better able to resist rutting and flow deformation.

[0076] (3) Rutting factor determination

[0077] The asphalt obtained in Examples 1-6 and Comparative Examples 1-9 was tested respectively, and two groups of samples were tested in parallel. The testing standard was "Testing Procedure for Asphalt and Asphalt Mixture in Highway Engineering" (JTG E20-2011). The results are as follows: Figure 2 shown.

[0078] Depend on Figure 2 It can be seen that with the increase of temperature, the rutting factors of different types of asphalt will gradually decrease; among them, compared with rubber asphalt (AR), the addition of deodorizer (corresponding to DAR) may lead to a slight decrease in its rutting factor, while the further addition of warm mix agent (corresponding to DWMAR) leads to a significant decrease in the rutting factor, and the ability to resist rutting deformation is significantly weakened.

[0079] (4) High temperature failure temperature determination

[0080] The asphalt obtained in Examples 1-6 and Comparative Examples 1-9 was tested respectively, and two groups of samples were tested in parallel. The testing standard was "Testing Procedure for Asphalt and Asphalt Mixture in Highway Engineering" (JTG E20-2011). The results are as follows: Figure 3 shown.

[0081] Depend on Figure 3 It can be seen that compared with rubber asphalt (AR), the high-temperature failure temperature of asphalt with warm mix agent (WMAR) is lower, indicating that warm mix agent can reduce the high-temperature resistance of asphalt.

[0082] At the same time, it can be seen that as the deodorant content increases, the high-temperature failure temperature of asphalt does not change much, indicating that the deodorant components and their chemical reactions have little effect on the high-temperature resistance of asphalt.

[0083] (5) Rotational viscosity measurement

[0084] The asphalt obtained in Examples 1-6 and Comparative Examples 1-9 was tested respectively, and two groups of samples were tested in parallel. The testing standard was "Testing Procedure for Asphalt and Asphalt Mixture in Highway Engineering" (JTG E20-2011). The results are as follows: Figure 4 shown.

[0085] Depend on Figure 4 It can be seen that with the increase of temperature, the rotational viscosity of different types of asphalt will gradually decrease; among them, compared with rubber asphalt (AR), the addition of deodorizer (corresponding to DAR) has relatively little effect on the rotational viscosity, and the rotational viscosity is significantly reduced after further adding warm mix agent (corresponding to DWMAR), and it has excellent anti-rutting performance under high temperature conditions.

[0086] Effect Example 2 Functional Group Analysis of Asphalt

[0087] Fourier transform infrared spectroscopy was performed on the asphalts obtained in Comparative Examples 1, 4, 7 and 9 respectively, and three groups were measured in parallel:

[0088] Grind each asphalt and infrared transparent material (such as KBr) evenly and press them into transparent sheets for measurement; each asphalt and KBr should be dried and ground to a particle size of less than 2 microns to avoid the influence of scattered light; the results are as follows: Figure 5-6 As shown (where Figure 5 This is the result of direct measurement by infrared spectroscopy. Figure 6 is the result after data processing such as automatic baseline correction and automatic smoothing).

[0089] Depend on Figure 5-6It can be seen that the basic characteristic functional groups of asphalt are n-alkanes, aromatics and amines; among them, most of the characteristic peaks of NA (M0), AR (M1), DAR-0.4% LD (M3) and DAR-0.4% PD (M4) are similar, that is, the addition of rubber powder and deodorant has little effect on the inherent properties and chemical composition of the base asphalt.

[0090] Effect Example 3 Determination of smoke component concentrations generated during asphalt heating

[0091] Different types of asphalt emit harmful gases when heated. These gases are caused by the volatile organic compounds (VOCs) in the asphalt. Different types of asphalt have different VOC content and composition, so they emit different levels of harmful gases when heated.

[0092] The present invention measures the asphalt obtained in Examples 1-18 and Comparative Examples 1-39 respectively, and measures four groups of samples in parallel by using an ultraviolet-visible spectrophotometer. The specific smoke components include: (1) ammonia; (2) nitrogen oxides; (3) hydrogen sulfide; and (4) sulfur dioxide. The determination of ammonia can be carried out with reference to the standard YC / T 377-2010; the determination of nitrogen oxides, hydrogen sulfide and sulfur dioxide can be carried out by conventional detection methods in the art.

[0093] The results are as follows Figure 7-16 shown.

[0094] Figure 7 are respectively the concentrations of ammonia generated during the heating of the asphalt obtained in Examples 1-6 and Comparative Examples 1-9, Figure 8 They are respectively the concentrations of ammonia generated during the heating of the asphalt obtained in Comparative Example 1 (DAR, i.e., AR, with a deodorant dosage of 0), Comparative Example 2 (DWMAR, i.e., WMAR, with a deodorant dosage of 0), Examples 1-6 and Comparative Examples 3-8.

[0095] Fig. 9 The concentrations of nitrogen oxides generated during the heating of the asphalt obtained in Examples 1-6 and Comparative Examples 1-9 are respectively, Fig.10 They are respectively the concentrations of nitrogen oxides generated during the heating of the asphalt obtained in Comparative Example 1 (DAR, i.e., AR, with a deodorant dosage of 0), Comparative Example 2 (DWMAR, i.e., WMAR, with a deodorant dosage of 0), Examples 1-6 and Comparative Examples 3-8.

[0096] Fig.11 are respectively the concentrations of hydrogen sulfide generated during the heating of the asphalt obtained in Examples 1-6 and Comparative Examples 1-9, Fig.12They are respectively the concentrations of hydrogen sulfide generated during the heating of the asphalt obtained in Comparative Example 1 (DAR, i.e., AR, with a deodorant dosage of 0), Comparative Example 2 (DWMAR, i.e., WMAR, with a deodorant dosage of 0), Examples 1-6 and Comparative Examples 3-8.

[0097] Fig.13 The sulfur dioxide concentrations generated during the heating of the asphalt obtained in Examples 1-6 and Comparative Examples 1-9 are respectively, Fig.14 They are respectively the concentrations of sulfur dioxide generated during the heating of the asphalt obtained in Comparative Example 1 (DAR, i.e., AR, with a deodorant dosage of 0), Comparative Example 2 (DWMAR, i.e., WMAR, with a deodorant dosage of 0), Examples 1-6 and Comparative Examples 3-8.

[0098] Figure 15-16 The concentrations of sulfur dioxide generated during the heating of the asphalt obtained in Examples 2, 5, 7-12 and Comparative Examples 1, 2, 4, 7, 9-39 are respectively.

[0099] Depend on Figure 7-14 It can be seen that the harmful gas emissions generated by rubber asphalt (AR) and rubber asphalt with further addition of warm mix agent (WMAR) when heated are significantly increased compared with base asphalt (NA); however, on the basis of rubber asphalt, the emission is significantly reduced after further addition of deodorant, and the effect of adding deodorant and warm mix agent at the same time is relatively optimal. It can be seen that even if the addition of warm mix agent will lead to an increase in harmful gas emissions, the deodorizing effect is further increased after further coupling with deodorant. And to a certain extent, the effect is relatively better after adding powdered deodorant.

[0100] Depend on Fig.15 It can be seen that as the mixing time increases, the asphalt will react more fully with the air and other gases, increasing the emission of harmful gases. However, under the same mixing time, the emissions of asphalt with the addition of warm mix agent and deodorizing agent (DWMAR) are significantly lower.

[0101] Depend on Fig.16 It can be seen that, except for rubber asphalt (WMAR) with added warm mix agent, for the same type of asphalt, the concentration of sulfur dioxide produced by the asphalt during the experiment will increase with the increase of stirring speed, indicating that the increase in stirring speed may cause the asphalt to receive more oxygen, thereby accelerating the reaction rate and sulfur dioxide emissions. However, at the same stirring speed, the emissions of asphalt (DWMAR) with the addition of warm mix agent and deodorizer are significantly lower.

[0102] In summary, the modified asphalt of the present invention, based on the existing odorless rubber asphalt, achieves comprehensive improvement in environmental protection performance, basic asphalt properties, and construction and workability by adding warm mix agents and optimizing the preparation process. The preparation process is simple, the operation and control are convenient, the equipment investment is small, the energy consumption is low, and it is suitable for continuous industrial production. It has significant technical advantages and promotion and application value.

Claims

1. A modified asphalt, characterized in that: The modified asphalt comprises the following components: base asphalt, rubber powder, warm mix agent and deodorant; wherein, Based on the weight of the matrix asphalt, the content of the rubber powder is 15%-20%, the content of the warm mix agent is 1%-5%, and the content of the deodorant is 0.1%-1%.

2. The modified asphalt according to claim 1, characterized in that The matrix asphalt is Jingbo 70 asphalt; And / or, in the modified asphalt, the weight percentage of the base asphalt is 90%-95%.

3. The modified asphalt according to claim 1, characterized in that The warm-mix agent includes one or more of a polyolefin warm-mix agent, a viscosity-reducing warm-mix agent and a surfactant-type warm-mix agent; preferably, the warm-mix agent includes one or more of WSG-H02, Sasoflex and Sasobit; And / or, based on the weight of the base asphalt, the content of the warm mix agent is 3%.

4. The modified asphalt according to claim 1, characterized in that The deodorant includes a liquid deodorant and / or a powdered deodorant; Wherein, the liquid deodorant preferably comprises alcohol, and the alcohol is more preferably plant alcohol and / or industrial alcohol; Wherein, the powdered deodorant preferably comprises a porous adsorbent material, such as one or more of activated carbon, zeolite, porous calcium phosphate and silica gel; And / or, based on the weight of the base asphalt, the content of the deodorant is 0.2%, 0.4% or 0.6%.

5. The modified asphalt according to claim 1, characterized in that In the modified asphalt, the weight ratio of the warm mix agent to the deodorizer is 2.5:1-15:1, preferably 2.5:1-10:1, such as 5:1 or 7.5:

1.

6. The modified asphalt according to claim 1, characterized in that The mesh number of the rubber powder is 40-80 mesh; And / or, the rubber powder is waste tire rubber powder.

7. A method for preparing the modified asphalt according to any one of claims 1 to 6, characterized in that: The preparation method of the modified asphalt comprises the following steps: The base asphalt is heated and mixed with the rubber powder, warm mix agent and deodorant to obtain the modified asphalt.

8. The method for preparing modified asphalt according to claim 7, characterized in that: After the base asphalt is heated, it is sequentially mixed with the rubber powder, warm mix agent and deodorizer; And / or, the heating temperature is 150-180° C., for example 170° C.; And / or, the mixing is stirring mixing; And / or, the mixing time is 0.5-3h; And / or, the mixing temperature is 150-180°C, for example 170°C; And / or, the mixing speed is 250-2000 rpm, such as 1000 rpm.

9. The method for preparing modified asphalt according to claim 7 or 8, characterized in that: The mixing step may be followed by a purification step; preferably, the purification step is performed by filtering.

10. Use of the modified asphalt according to any one of claims 1 to 6 in a road paving structure.

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